📢 Too many exams? Don’t know which one suits you best? Book Your Free Expert 👉 call Now!


    Question

    A boat covers 36 km downstream in 3 hours and 24 km

    upstream in 4 hours. Find the speed of the boat in still water and the speed of the stream.
    A 11 km/h and 2 km/h Correct Answer Incorrect Answer
    B 7 km/h and 1 km/h Correct Answer Incorrect Answer
    C 9 km/h and 3 km/h Correct Answer Incorrect Answer
    D 5 km/h and 3 km/h Correct Answer Incorrect Answer

    Solution

    Downstream speed = 36/3 = 12 km/h Upstream speed = 24/4 = 6 km/h Let boat speed in still water = u, stream speed = v. u + v = 12 u − v = 6 Add: 2u = 18 ⇒ u = 9 km/h Then v = 12 − 9 = 3 km/h Answer: Boat speed = 9 km/h, Stream speed = 3 km/h.

    Practice Next

    Relevant for Exams:

    ask-question